1.
1
ANURAG COLLEGE OF ENGINEERING
Aushapur(V), Ghatkesar(M), Medchal(D),T.S
DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING
BLOCKCHAIN TECHNOLOGY
Under the guidance of :-
Mrs. M. Prasanna
Assistant Professor
Presented by:
MD. IQBAL MATHEEN 20PQ5A0505

2.
BLOCKCHAIN TECHNOLOGY
MD Iqbal Matheen

3.
CONTENTS
BLOCKCHAIN TECHNOLOGY 3
Introduction
Why
Blockchain?
Cryptography
in Blockchain
Nodes
Hashing Merkle Tree
Blockchain
Architecture
Types of
Blockchain
Proof of Work Advantages Disadvantages Applications
Conclusion Future Scope Bibliography

4.
INTRODUCTIO
N
• If you have heard about Bitcoins, you might have
heard about BLOCKCHAIN as well.
• The work on bitcoin started on 2008 by Satoshi
Nakamoto has created Bitcoin using BLOCKCHAIN, it
is a pear to pear network.
• There is no central system ie, no bank in between,
everything distributed.
• A BLOCKCHAIN is a distributed ledger
technology (DTL) that consists of growing lists of
records called as BLOCKS, they are securely
linked together using cryptography.
• Each block contains a cryptography hash of
previous block.
• Since each block contains information about
previous block they effectively forms a chain called
as 'BLOCKCHAIN'
• Consequently, blockchain transactions are
irreversible once they recorded cannot be altered.

5.
WHY
BLOCKCHAIN?
Why it is famous ?

6.
WHY
BLOCKCHAIN
?
• Decentralized in design
• Provides trust
• Immutability
• Secure
BLOCKCHAIN TECHNOLOGY 6

7.
CRYPTOGRAPHY IN
BLOCKCHAIN
SECURITY & PRIVACY
BLOCKCHAIN TECHNOLOGY
7

8.
SECURITY &
PRIVACY
• Since BLOCKCHAIN is a
Peer-to-Peer Network, we
have four big concerns:
• Confidentiality
• Integrity
• Non repudiation
• Authentication
BLOCKCHAIN TECHNOLOGY 8

9.
CONFIDENTIALITY
• To achieve confidentiality we cryptography, we
use encryption and decryption.
• Encryption and Decryption is done with the
help of a KEY.
• Symmetric Key Cryptography, Asymmetric
Key Cryptography.
• In Symmetric Key Cryptography there is only
one key for both the encryption and
decryption.
• In Asymmetric Key
Cryptography there are two keys (Private Key
& Public key) for the encryption and
decryption.

10.
AUTHENTICATION
• To achieve the authentication we had
a concept called DIGITAL
SIGNATURE.
• For example A is sending
a message to B, A encrypts the
message using its private key and
then B decrypts the message using
the A's public key.
• Here A will have a digital
signature with the A's private key,
that is how B will knows it was sent by
A and decrypts using A's public
key. But we lose confidentiality
for this we use double encryption.

11.
NODES
• There are two types of Nodes
they are:
• Full Node
• Partial Node
• The full node will store the
entire BLOCKCHAIN &
verifies the blocks then it
stores the blocks. It verifies
the transaction.
• Partial node will have some
part of a BLOCKCHAIN since
blockchain is a
very huge data. It is only for
wallet purpose.
BLOCKCHAIN TECHNOLOGY 11

12.
HASHING
• Hashing is a technique that it takes the
input string of any length and converts it
to a fixed length output string.
• The fixed length output string is known as
hash value.
• For hashing it uses some algorithms like
MD(MD2 MD3... MD6), SHA1, SHA2,
SHA3.
• If we change small value in the input
string, it changes the whole hash value.
• We cannot get the actual input string
using the hash value. Since it loses the
data.
• Hashing is not an encryption.
• For two different inputs it will give two
different hash values. If it gives same
hash value, it is called as Collision. BLOCKCHAIN TECHNOLOGY 12

13.
MERKLE TREE
• In blockchain every block is
connected with each other
with the help of hash values.​
• Every block contains no of
transactions, contains no of
hashes.​
• To find a single hash in the
block it is difficult to search,
so blockchain
implements MERKLE TREE.
• It
contains root, branches, leaf
nodes.
BLOCKCHAIN TECHNOLOGY

14.
BLOCKCHAIN
ARCHITECTURE
BLOCKCHAIN TECHNOLOGY
• Nodes within P2P
network
• Properties of block &
genesis block
• Transactions within the
ledger
• The validation process -
mining
• The “consensus” within a
blockchain architecture
• Proof-of-work
14

15.
TYPES OF
BLOCKCHAI
N
BLOCKCHAIN TECHNOLOGY 15
Public Blockchain
Private Blockchain
Federated Blockchain

16.
PROOF OF
WORK
• Proof of Work(POW) is the original
consensus algorithm in a
blockchain network.
• The algorithm is used to confirm
the transaction and creates a new
block to the chain.
• In this algorithm, minors (a group
of people) compete against each
other to complete the transaction
on the network.
• The process of competing against
each other is called mining.
• As soon as miners successfully
created a valid block, he
gets rewarded.
• The most famous application of
Proof of Work(PoW) is Bitcoin.
16 BLOCKCHAIN TECHNOLOGY

17.
ADVANTAGES
OF
BLOCKCHAIN
BLOCKCHAIN TECHNOLOGY 17
Open
Verifiable
Permanent
Tighter Security
Immutability
Efficiency
Cost Reduction

18.
DISADVANTAGES OF BLOCKCHAIN
BLOCKCHAIN
TECHNOLOGY
18
Complex Slow Wastage of
Resources
Security/Privacy 51% Attack

19.
APPLICATIONS
OF BLOCKCHAIN
• Cryptocurrency
• Asset Management
• Cross – Border Payments
• Healthcare
• Online Identity Verification
• Internet of Things
• Copyright and Royalities
BLOCKCHAIN TECHNOLOGY 19

20.
CONCLUSION
• In this short tutorial you were introduced to several
concepts of Blockchain.
• The Bitcoin is the first successful implementation of
blockchain.
• Today, the world has found applications of
blockchain technology in several industries, where
the trust without the involvement of a centralized
authority is desired.
• So welcome to the world of Blockchain.
BLOCKCHAIN TECHNOLOGY 20

21.
FUTURE SCOPE
• Blockchain technology gave us Bitcoin, the ultimate cryptocurrency. Soon, the
technological innovators of the world concentrated their energies on this breakthrough and
changed our understanding of currency and value transactions.
• Today, there are tens of thousands of digital currencies and tokens that are challenging
the legacy financial system with decentralization.
• It will be a long-standing debate whether cryptocurrencies will replace fiat currencies or
not, but will blockchain technology shape the future of our industries? The answer is a
resounding yes.
BLOCKCHAIN TECHNOLOGY 21

22.
BIBLIOGRAPHY
• https://www.geeksforgeeks.org
/blockchain-technology-
introduction/
• https://www.javatpoint.com/blo
ckchain-tutorial
• https://www.youtube.com/watc
h?v=2uYuWiICCM0&list=PLsy
eobzWxl7oY6tZmnZ5S7yTDxy
u4zDW-
BLOCKCHAIN TE CHNOLOGY 22

23.
QUERIES ?
BLOCKCHAIN TECHNOLOGY 23

24.
THANK YOU
BLOCKCHAIN TECHNOLOGY 24